同时移动 2 个物体

Question

在我当前的 ios 项目中，我将屏幕的一侧专用于一个对象，将屏幕的另一侧专用于另一个对象，我已经做到了，如果您在屏幕的一侧滑动手指指定的对象会移动。但是，我想这样做，以便您可以同时以不同的运动移动两个对象，但我不知道该怎么做。以下是我当前的代码。

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint location = [touch locationInView:touch.view];

    if (location.x <= 270 ) {
        [Person setCenter:CGPointMake(location.x, Person.center.y)];

    }
    else  {
        [Person1 setCenter:CGPointMake(location.x, Person1.center.y)];
    }
}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint location = [touch locationInView:touch.view];

    if (location.x <= 270 ) {
        [Person setCenter:CGPointMake(location.x, Person.center.y)];
    }
    else  {
        [Person1 setCenter:CGPointMake(location.x, Person1.center.y)];
    }
}

Answer 1

您应该开始处理 touches 集合中传递的多个触摸 - 循环遍历所有 UITouch 对象并进行处理。

编辑： 这是你的代码：

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    for(UITouch *touch in [event allTouches]) {
        CGPoint location = [touch locationInView:touch.view];

        if (location.x <= 270 ) {
            [Person setCenter:CGPointMake(location.x, Person.center.y)];
        }
        else  {
            [Person1 setCenter:CGPointMake(location.x, Person1.center.y)];
        }
    }
}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
    for(UITouch *touch in [event allTouches]) {
        CGPoint location = [touch locationInView:touch.view];

        if (location.x <= 270 ) {
            [Person setCenter:CGPointMake(location.x, Person.center.y)];
        }
        else  {
            [Person1 setCenter:CGPointMake(location.x, Person1.center.y)];
        }
    }
}

Answer 2

如果您将 -touchesBegan 和 touchesMoved 代码移动到 Person 视图类而不是当前所在的视图/或 viewController 类中，那么这些视图可以彼此独立地同时处理触摸。

*编辑：更多信息： 目前，您正在使用上面粘贴的代码处理触摸事件（我猜是 UIViewController），如果您将该代码移动到您创建的 Person 类中，您可以使代码更简单并实现您想要的结果。 这将产生这样的效果，即 Person 将决定它是否被触摸以及在哪里被触摸，并将相应地移动自己。

在您的 Person.m 文件中添加此代码，

 -(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint location = [touch locationInView:self.superview];
    [self moveToLocation:location];
}

-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint location = [touch locationInView:self.superview];
    [self moveToLocation:location];
}

-(void)moveToLocation:(CGPoint)location{
    CGFloat halfOfPersonWidth = self.bounds.size.width /2.0f;
    CGFloat halfOfSuperviewWidth = self.superview.bounds.size.width/2.0f;

    // Stop Person from going off left screen edge
    if ((location.x - halfOfPersonWidth) <= 0.0f){
        return;
    } // Stop Person from going off right screen edge
    else if ((location.x + halfOfPersonWidth) >= self.superview.bounds.size.width){
        return;
    }

    if (self.center.x < halfOfSuperviewWidth) {
        // Person is on the left of the screen and should not move to right side
        if ((location.x + halfOfPersonWidth) > halfOfSuperviewWidth) {
             return;
        }
    } else{
        // Person is on the right of the screen and should not move to left side
        if ((location.x - halfOfPersonWidth) < halfOfSuperviewWidth) {
            return;
        }
    }
    // If we have made it this far then we can move the Person
    // move to touch location on x axis only
    [self setCenter:CGPointMake(location.x, self.center.y)];
    }

现在在您的 View Controller 类中，您可以删除您在此处粘贴的原始 -touchesBegan 和 -touchesMoved 代码，或者如果您要谨慎，只需将其注释掉

 /* put slash asterisks above the code and asterisks slash below the code to comment out */

如果您构建并运行，您应该能够像以前一样移动每个 Person 视图，但如果您同时将手指放在每个 Person 视图上，您​​应该能够同时移动它们。